The heart is a four-chambered muscle that pumps blood through your body. Normally the contraction of heart muscle is well regulated. Muscle fibers surrounding a chamber contract in unison (all at the same time) and the different chambers work together to move the blood. The electrical impulses that bring about this coordination sometimes, however, fail. It is possible to keep a person alive and even restore him to normal activity by providing correct impulses from some artificial source. This is what a cardiac pacemaker does.
The first pacemakers were large devices that stimulated the heart through large electrodes (metal pieces for electrical contact) placed on the chest. In 1952 Paul M. Zoll, working with engineers of the Electrodyne Company, developed the first successful external pacemaker. Because large impulses were required, use of the device caused pain and burns. In 1957 a somewhat better device was created, which was implanted in the chest and used smaller impulses. The obvious drawback was that the chest needed to be opened and wires run to an external pulse generator.
In the last month of 1957 and the first months of 1958 the engineer
Earl Bakken designed and built a transistorized pacemaker. The transistor revolutionized electronics in all industries including the medical industry, by allowing things to be made smaller. In 1958 and 1959 the engineer Wilson Greatbatch and the cardiologist W.M. Chardack developed a fully implantable pacemaker (that is, it could be placed on top of the heart). Six years later Greatbatch improved on the design by making a so-called inhibited demand pacemaker. It provided impulses to the heart only when they were needed. Since then, many further improvements have been made, and today cardiac pacemakers enable millions of people to lead normal lives.
Earl Bakken’s prototype pacemaker was first used on patients in 1958.
It ran on batteries and was used on patients whose hearts failed to begin beating after surgery.
Courtesy: Bakken Library and Museum.
A modern day artifical pacemaker
Pacemaker History
On October 8th, 1958 the first pacemaker implantation was performed in Sweden. The system had been developed by the surgeon Ake Senning and the physician inventor Rune Elmqvist and implanted on a 43-year old engineer called Arne Larsson.
The entire unit was entirely hand-made and consisted of the nickel-cadmium batteries, the electronic circuit and the coil recharging antenna. These were encapsulated in a new epoxy resin (Araldite) produced by Ciba-Geigy, which had excellent biocompatibility. The approximate diameter and thickness became 55 mm and 16 mm respectively.
The first implanted artificial pacemaker
As technology evolved, so did pacemaking.
Fortunately, medicine and science have come a long way since the 50's and 60's. Todays pacemakers are smaller and considerably more reliable.
Contemporary Pacemaker (left) and Device Readers (Right)
With the invent of the internet, Pacemakers can now be monitored remotely, by uploading data telephonically to a central server.
Cross-Section of a modern Lithium Battery powered Artificial Pacemaker.
This information is an extract of a full historical account of the evolution of the artificial pacemaker from Impaedcard (Images in Paediatric Cardiology. This article can be viewed in it's entirety by clicking HERE. Alternatively, the full article can be downloaded from Impaedcard HERE, or from our server (Faster) HERE.
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